The endovascular treatment of a variety of conditions throughout the body is an increasingly more important form of therapy. One such procedure uses embolization coils to occlude a target site by forming a physical barrier to blood flow and/or by promoting thrombus formation at the site. Such treatments can be useful where it is desired to reduce vascularization, including treatments for aneurisms and cancer.
Coils have typically been placed at the desired site within the vasculature using a catheter and a delivery device such as a pusher member. As a first step, a flexible, small diameter catheter can be guided to the target site through the use of a guidewire or by other means. Once the site has been reached, the catheter lumen is cleared by removing the guidewire (if a guidewire has been used), and the coil is placed into the proximal open end of the catheter and advanced through the catheter via the delivery device, which has a distal end that is adapted to engage and push the coil through the catheter lumen as the delivery device is advanced through the catheter. When the coil reaches the distal end of the catheter, it is discharged from the catheter by the delivery device into the vascular site.
Several techniques have been developed to enable more accurate placement of coils within a vessel, including techniques where the delivery device is temporarily affixed to the coil, and which can be released via electrical (e.g., electrolytic dissolution) and mechanical means (e.g., interlocking members operated by an activation wire).
The present disclosure pertains to improved devices, systems and methods for implantable device delivery.